[net-next,v4,2/6] net: dcb: add new apptrust attribute

Message ID 20221028100320.786984-3-daniel.machon@microchip.com
State New
Headers
Series Add new PCP and APPTRUST attributes to dcbnl |

Commit Message

Daniel Machon Oct. 28, 2022, 10:03 a.m. UTC
  Add new apptrust extension attributes to the 8021Qaz APP managed object.

Two new attributes, DCB_ATTR_DCB_APP_TRUST_TABLE and
DCB_ATTR_DCB_APP_TRUST, has been added. Trusted selectors are passed in
the nested attribute DCB_ATTR_DCB_APP_TRUST, in order of precedence.

The new attributes are meant to allow drivers, whose hw supports the
notion of trust, to be able to set whether a particular app selector is
trusted - and in which order.

Signed-off-by: Daniel Machon <daniel.machon@microchip.com>
---
 include/net/dcbnl.h        |  4 ++
 include/uapi/linux/dcbnl.h | 10 +++++
 net/dcb/dcbnl.c            | 78 +++++++++++++++++++++++++++++++++++++-
 3 files changed, 90 insertions(+), 2 deletions(-)
  

Comments

Petr Machata Oct. 31, 2022, 12:24 p.m. UTC | #1
Daniel Machon <daniel.machon@microchip.com> writes:

> +	if (ieee[DCB_ATTR_DCB_APP_TRUST_TABLE]) {
> +		u8 selectors[IEEE_8021QAZ_APP_SEL_MAX + 1] = {0};
> +		struct nlattr *attr;
> +		int nselectors = 0;
> +		u8 selector;
> +		int rem, i;
> +
> +		if (!ops->dcbnl_setapptrust) {
> +			err = -EOPNOTSUPP;
> +			goto err;
> +		}
> +
> +		nla_for_each_nested(attr, ieee[DCB_ATTR_DCB_APP_TRUST_TABLE],
> +				    rem) {
> +			if (nla_type(attr) != DCB_ATTR_DCB_APP_TRUST ||
> +			    nla_len(attr) != 1 ||
> +			    nselectors >= sizeof(selectors)) {
> +				err = -EINVAL;
> +				goto err;
> +			}
> +
> +			selector = nla_get_u8(attr);
> +			switch (selector) {
> +			case IEEE_8021QAZ_APP_SEL_ETHERTYPE:
> +			case IEEE_8021QAZ_APP_SEL_STREAM:
> +			case IEEE_8021QAZ_APP_SEL_DGRAM:
> +			case IEEE_8021QAZ_APP_SEL_ANY:
> +			case IEEE_8021QAZ_APP_SEL_DSCP:
> +			case DCB_APP_SEL_PCP:

This assumes that the range of DCB attributes will never overlap with
the range of IEEE attributes. Wasn't the original reason for introducing
the DCB nest to not have to make this assumption?

I.e. now that we split DCB and IEEE attributes in the APP_TABLE
attribute, shouldn't it be done here as well?
  
Daniel Machon Oct. 31, 2022, 12:45 p.m. UTC | #2
> > +     if (ieee[DCB_ATTR_DCB_APP_TRUST_TABLE]) {
> > +             u8 selectors[IEEE_8021QAZ_APP_SEL_MAX + 1] = {0};
> > +             struct nlattr *attr;
> > +             int nselectors = 0;
> > +             u8 selector;
> > +             int rem, i;
> > +
> > +             if (!ops->dcbnl_setapptrust) {
> > +                     err = -EOPNOTSUPP;
> > +                     goto err;
> > +             }
> > +
> > +             nla_for_each_nested(attr, ieee[DCB_ATTR_DCB_APP_TRUST_TABLE],
> > +                                 rem) {
> > +                     if (nla_type(attr) != DCB_ATTR_DCB_APP_TRUST ||
> > +                         nla_len(attr) != 1 ||
> > +                         nselectors >= sizeof(selectors)) {
> > +                             err = -EINVAL;
> > +                             goto err;
> > +                     }
> > +
> > +                     selector = nla_get_u8(attr);
> > +                     switch (selector) {
> > +                     case IEEE_8021QAZ_APP_SEL_ETHERTYPE:
> > +                     case IEEE_8021QAZ_APP_SEL_STREAM:
> > +                     case IEEE_8021QAZ_APP_SEL_DGRAM:
> > +                     case IEEE_8021QAZ_APP_SEL_ANY:
> > +                     case IEEE_8021QAZ_APP_SEL_DSCP:
> > +                     case DCB_APP_SEL_PCP:
> 
> This assumes that the range of DCB attributes will never overlap with
> the range of IEEE attributes. Wasn't the original reason for introducing
> the DCB nest to not have to make this assumption?
> 
> I.e. now that we split DCB and IEEE attributes in the APP_TABLE
> attribute, shouldn't it be done here as well?

Hmm, doesn't hurt to do strict checking here as well. We can even get rid
of the DCB_ATTR_DCB_APP_TRUST attr and just pass DCB_ATTR_DCB_APP and
DCB_ATTR_IEEE_APP? Then use the same functions to do the checking.

/ Daniel
  
Petr Machata Oct. 31, 2022, 4:24 p.m. UTC | #3
<Daniel.Machon@microchip.com> writes:

>> > +     if (ieee[DCB_ATTR_DCB_APP_TRUST_TABLE]) {
>> > +             u8 selectors[IEEE_8021QAZ_APP_SEL_MAX + 1] = {0};
>> > +             struct nlattr *attr;
>> > +             int nselectors = 0;
>> > +             u8 selector;
>> > +             int rem, i;
>> > +
>> > +             if (!ops->dcbnl_setapptrust) {
>> > +                     err = -EOPNOTSUPP;
>> > +                     goto err;
>> > +             }
>> > +
>> > +             nla_for_each_nested(attr, ieee[DCB_ATTR_DCB_APP_TRUST_TABLE],
>> > +                                 rem) {
>> > +                     if (nla_type(attr) != DCB_ATTR_DCB_APP_TRUST ||
>> > +                         nla_len(attr) != 1 ||
>> > +                         nselectors >= sizeof(selectors)) {
>> > +                             err = -EINVAL;
>> > +                             goto err;
>> > +                     }
>> > +
>> > +                     selector = nla_get_u8(attr);
>> > +                     switch (selector) {
>> > +                     case IEEE_8021QAZ_APP_SEL_ETHERTYPE:
>> > +                     case IEEE_8021QAZ_APP_SEL_STREAM:
>> > +                     case IEEE_8021QAZ_APP_SEL_DGRAM:
>> > +                     case IEEE_8021QAZ_APP_SEL_ANY:
>> > +                     case IEEE_8021QAZ_APP_SEL_DSCP:
>> > +                     case DCB_APP_SEL_PCP:
>> 
>> This assumes that the range of DCB attributes will never overlap with
>> the range of IEEE attributes. Wasn't the original reason for introducing
>> the DCB nest to not have to make this assumption?
>> 
>> I.e. now that we split DCB and IEEE attributes in the APP_TABLE
>> attribute, shouldn't it be done here as well?
>
> Hmm, doesn't hurt to do strict checking here as well. We can even get rid
> of the DCB_ATTR_DCB_APP_TRUST attr and just pass DCB_ATTR_DCB_APP and
> DCB_ATTR_IEEE_APP? Then use the same functions to do the checking.

That would make sense to me.
  

Patch

diff --git a/include/net/dcbnl.h b/include/net/dcbnl.h
index 2b2d86fb3131..8841ab6c2de7 100644
--- a/include/net/dcbnl.h
+++ b/include/net/dcbnl.h
@@ -109,6 +109,10 @@  struct dcbnl_rtnl_ops {
 	/* buffer settings */
 	int (*dcbnl_getbuffer)(struct net_device *, struct dcbnl_buffer *);
 	int (*dcbnl_setbuffer)(struct net_device *, struct dcbnl_buffer *);
+
+	/* apptrust */
+	int (*dcbnl_setapptrust)(struct net_device *, u8 *, int);
+	int (*dcbnl_getapptrust)(struct net_device *, u8 *, int *);
 };
 
 #endif /* __NET_DCBNL_H__ */
diff --git a/include/uapi/linux/dcbnl.h b/include/uapi/linux/dcbnl.h
index dc7ef96207ca..9344e3ba5768 100644
--- a/include/uapi/linux/dcbnl.h
+++ b/include/uapi/linux/dcbnl.h
@@ -410,6 +410,7 @@  enum dcbnl_attrs {
  * @DCB_ATTR_IEEE_PEER_ETS: peer ETS configuration - get only
  * @DCB_ATTR_IEEE_PEER_PFC: peer PFC configuration - get only
  * @DCB_ATTR_IEEE_PEER_APP: peer APP tlv - get only
+ * @DCB_ATTR_DCB_APP_TRUST_TABLE: selector trust table
  */
 enum ieee_attrs {
 	DCB_ATTR_IEEE_UNSPEC,
@@ -423,6 +424,7 @@  enum ieee_attrs {
 	DCB_ATTR_IEEE_QCN,
 	DCB_ATTR_IEEE_QCN_STATS,
 	DCB_ATTR_DCB_BUFFER,
+	DCB_ATTR_DCB_APP_TRUST_TABLE,
 	__DCB_ATTR_IEEE_MAX
 };
 #define DCB_ATTR_IEEE_MAX (__DCB_ATTR_IEEE_MAX - 1)
@@ -435,6 +437,14 @@  enum ieee_attrs_app {
 };
 #define DCB_ATTR_IEEE_APP_MAX (__DCB_ATTR_IEEE_APP_MAX - 1)
 
+enum dcbnl_attrs_apptrust {
+	DCB_ATTR_DCB_APP_TRUST_UNSPEC,
+	DCB_ATTR_DCB_APP_TRUST,
+	__DCB_ATTR_DCB_APP_TRUST_MAX
+};
+
+#define DCB_ATTR_DCB_APP_TRUST_MAX (__DCB_ATTR_DCB_APP_TRUST_MAX - 1)
+
 /**
  * enum cee_attrs - CEE DCBX get attributes.
  *
diff --git a/net/dcb/dcbnl.c b/net/dcb/dcbnl.c
index 68e033a459af..a56f401aeec4 100644
--- a/net/dcb/dcbnl.c
+++ b/net/dcb/dcbnl.c
@@ -166,6 +166,7 @@  static const struct nla_policy dcbnl_ieee_policy[DCB_ATTR_IEEE_MAX + 1] = {
 	[DCB_ATTR_IEEE_QCN]         = {.len = sizeof(struct ieee_qcn)},
 	[DCB_ATTR_IEEE_QCN_STATS]   = {.len = sizeof(struct ieee_qcn_stats)},
 	[DCB_ATTR_DCB_BUFFER]       = {.len = sizeof(struct dcbnl_buffer)},
+	[DCB_ATTR_DCB_APP_TRUST_TABLE] = {.type = NLA_NESTED},
 };
 
 /* DCB number of traffic classes nested attributes. */
@@ -1081,9 +1082,9 @@  static int dcbnl_build_peer_app(struct net_device *netdev, struct sk_buff* skb,
 /* Handle IEEE 802.1Qaz/802.1Qau/802.1Qbb GET commands. */
 static int dcbnl_ieee_fill(struct sk_buff *skb, struct net_device *netdev)
 {
-	struct nlattr *ieee, *app;
-	struct dcb_app_type *itr;
 	const struct dcbnl_rtnl_ops *ops = netdev->dcbnl_ops;
+	struct nlattr *ieee, *app, *apptrust;
+	struct dcb_app_type *itr;
 	int dcbx;
 	int err;
 
@@ -1185,6 +1186,29 @@  static int dcbnl_ieee_fill(struct sk_buff *skb, struct net_device *netdev)
 	spin_unlock_bh(&dcb_lock);
 	nla_nest_end(skb, app);
 
+	if (ops->dcbnl_getapptrust) {
+		u8 selectors[IEEE_8021QAZ_APP_SEL_MAX + 1] = {0};
+		int nselectors, i;
+
+		apptrust = nla_nest_start(skb, DCB_ATTR_DCB_APP_TRUST_TABLE);
+		if (!app)
+			return -EMSGSIZE;
+
+		err = ops->dcbnl_getapptrust(netdev, selectors, &nselectors);
+		if (!err) {
+			for (i = 0; i < nselectors; i++) {
+				err = nla_put_u8(skb, DCB_ATTR_DCB_APP_TRUST,
+						 selectors[i]);
+				if (err) {
+					nla_nest_cancel(skb, apptrust);
+					return err;
+				}
+			}
+		}
+
+		nla_nest_end(skb, apptrust);
+	}
+
 	/* get peer info if available */
 	if (ops->ieee_peer_getets) {
 		struct ieee_ets ets;
@@ -1571,6 +1595,56 @@  static int dcbnl_ieee_set(struct net_device *netdev, struct nlmsghdr *nlh,
 		}
 	}
 
+	if (ieee[DCB_ATTR_DCB_APP_TRUST_TABLE]) {
+		u8 selectors[IEEE_8021QAZ_APP_SEL_MAX + 1] = {0};
+		struct nlattr *attr;
+		int nselectors = 0;
+		u8 selector;
+		int rem, i;
+
+		if (!ops->dcbnl_setapptrust) {
+			err = -EOPNOTSUPP;
+			goto err;
+		}
+
+		nla_for_each_nested(attr, ieee[DCB_ATTR_DCB_APP_TRUST_TABLE],
+				    rem) {
+			if (nla_type(attr) != DCB_ATTR_DCB_APP_TRUST ||
+			    nla_len(attr) != 1 ||
+			    nselectors >= sizeof(selectors)) {
+				err = -EINVAL;
+				goto err;
+			}
+
+			selector = nla_get_u8(attr);
+			switch (selector) {
+			case IEEE_8021QAZ_APP_SEL_ETHERTYPE:
+			case IEEE_8021QAZ_APP_SEL_STREAM:
+			case IEEE_8021QAZ_APP_SEL_DGRAM:
+			case IEEE_8021QAZ_APP_SEL_ANY:
+			case IEEE_8021QAZ_APP_SEL_DSCP:
+			case DCB_APP_SEL_PCP:
+				break;
+			default:
+				err = -EINVAL;
+				goto err;
+			}
+			/* Duplicate selector ? */
+			for (i = 0; i < nselectors; i++) {
+				if (selectors[i] == selector) {
+					err = -EINVAL;
+					goto err;
+				}
+			}
+
+			selectors[nselectors++] = selector;
+		}
+
+		err = ops->dcbnl_setapptrust(netdev, selectors, nselectors);
+		if (err)
+			goto err;
+	}
+
 err:
 	err = nla_put_u8(skb, DCB_ATTR_IEEE, err);
 	dcbnl_ieee_notify(netdev, RTM_SETDCB, DCB_CMD_IEEE_SET, seq, 0);